## 519 Reputation

14 years, 129 days

## Yes, you are right as always...

Yes your first code do the work (sorry). I have not understand the effect of the frequency.

I am very happy, thank you

## plot a function at the radius R...

@acer : Thanks for the answer:

I want to plot a function where the axis of abscisse theta is the radius R (for example cos(theta)). As in the figure below in red.

## The theta axis shoud be the contour of r...

But, I want plot the function cos(theta) where the axis theta of the function is represented by the contour (perimeter) of radius R (not inside the circle). I do not know if my explanations are good.

## matrixplot heights=histogram...

Thank you

The command

plots:-matrixplot( Y, heights=histogram, gap=0.5,
color=((x,y)->1-y/3+0.2),
orientation=[-55,55,0], labels=["","",""] );

is what I want.

## Maple 18...

I have Maple 18 and I can not find the command.

dataplot does not exists in Maple 18

## DiscreteTransforms...

@Markiyan Hirnyk @Carl Love 8142: Thank you

Yes, OrthogonalExpansions package can be used to determine 2D Fourier series coefficients. Now, I can read the help from Maple18.

From DiscreteTransforms, are matrices (3) and (4) represent the coefficients of 2D Fourier expansion ?  The matrices are the Fourier transform and we need to do an inverse Fourier transform to get the coefficients ?

Can you help me to plot the 2D Fourier expansion function issued from Discrete Transforms with the original function f(x,y).

Thank you

## OrthogonalExpansion not the solution...

I am using OrthogonalExpansion currently. It can not give the Fourier expansion from 2D Fourier transform.

I want to use 2D Fourier transform to obtain the coefficients of the 2D Fourier expansion of a surface as done in http://www.mapleprimes.com/questions/121551-Fourier-Serie-And-Discrete-Fourier-Transform for curves.

Thank you.

## Yes, it is simple...

Thank you.

Yes this work around solution allows end time simulation completed to 0.04s

But It is not a good solution. How to explain this add on to my students and for me too

Is there an other way ?

Thanks you again

Yes this work around solution allows end time simulation completed to 0.04s

But It is not a good solution. How to explain this add on to my students and for me too

Is there an other way ?

Thanks you again

## Yes, but...

But, The result seem to me wrong. Could you see the code attached ?